By Kevin Foley
Representatives from the New York State Department of Environmental Conservation (DEC) briefed Cold Spring’s Special Board for a Comprehensive Plan/Local Waterfront Revitalization Plan last week on the department’s green infrastructure initiatives and the importance of developing green alternatives to traditional methods of handling storm water runoff, particularly for Hudson River watershed communities. The meeting took place on March 24 at the Village Hall. Lacking a quorum to conduct other business, the four (of nine) Special Board members present— Chairman Michael Armstrong, Anne Impellizzeri, Marge Early and Karen Doyle—devoted the entire meeting to the DEC presentation and subsequent discussion.
Emily Vail, a watershed outreach specialist in the DEC’s Hudson River Estuary Program, explained that the program seeks to ensure clean water, protect and restore fish and wildlife habitats, provide recreation in and on the water, adapt to climate change, and conserve the scenic landscape. Created in 1987 and currently a partnership with the New York State Water Resources Institute of Cornell University, the program works with a variety of other state, federal, and local agencies, as well as with other public-private partnerships to achieve its goals, according to Vail. Storm water runoff from communities adjoining the Hudson has an enormous impact on the river’s cleanliness and the condition of wildlife habitats, said Vail. Water runoff can carry many types of polluting materials and chemicals such as heavy metals, pesticides, oil and grease, road salt, animal and human waste and other assorted trash into the river. She said the introduction of green or more natural solutions to managing storm water is an important component not only in protecting the river but also in aiding local flood prevention, slowing soil erosion and retaining storm water for reuse on lawns and gardens or for other purposes.
Part of the problem with prevailing storm water management systems is their relentless efficiency, explained Vail. Impervious concrete, asphalt or other surfaces on roads, driveways, parking lots and rooftops all smoothly drive water away from homes and business toward drainage pipes and streams with the water gathering force along the way. The volume and force of running storm water can erode stream banks, clog culverts and pipes, and over-tax sewage treatment facilities. At these facilities, the flow is combined; causing flooding and giving refuse a swift and destructive ride to the river. “In a natural area approximately 10 percent of the water from a rainfall becomes runoff. In a more paved or urban-type setting, as much as 55 percent of the water from a storm can become runoff, leaving a very high volume of above-ground water to be dealt with,” said Vail.
Vail said the DEC believes green infrastructure projects can serve as a natural alternative to current water-control methods principally by capturing far more water where it falls or along the way before it enters pipes or streams. According to Vail, beginning March 1 the DEC review process for all new development projects mandates the incorporation of natural storm water management solutions in design plans. “Green infrastructure is defined as a network of naturally occurring and engineered systems in the environment, generally vegetated, that provide eco-system services. For storm water that means restoring natural hydrology”¦ having the water go into the ground rather than shunting it off into a pipe and having it go into a stream,” said Vail.
According to Vail, the DEC encourages communities to include green infrastructure practices in planning processes to reduce storm water volume beginning with the preservation of natural areas as a planning priority for new development. This also involves keeping as many trees as possible on development sites, preserving and using undisturbed areas as buffers, and restoring soil affected by heavy machinery. Vail showed a picture of a parking lot where water was directed to a garden rather than a drainage system to illustrate how small-scale projects can have a large impact on water flow when replicated throughout a community.
Aside from controlling storm water flow and volume, Vail said other benefits include improved water quality; enhanced wildlife through the use of native plants; and an improvement in aesthetic experience. “Using plants and flowers instead of pipes underground can be a real resource for communities,” she said. Storm water can be better controlled when green infrastructure practices, such as rain gardens with specially chosen plants, are deployed to receive storm water on site rather than running it off, Vail explained. More complex gardens called bio-retention areas operate on similar principles and can be installed in large-scale developments. Vail said the Beacon Institute developed one at their Dennings Point facility in Beacon, N.Y.
Green roofs where vegetation captures and retains rain rather than sending it down gutters are a new but increasingly popular concept with only a few examples in the Hudson Valley, said Vail. Mike Armstrong pointed out the roof of the Chancery building adjacent to the Chapel of Our Lady Restoration at the train station in Cold Spring as a local example of garden roofs. Vail said reducing the amount of impervious surface cover resulting from building sidewalks, driveways, rooftops and parking lots wherever possible is the DEC’s next community priority in limiting storm water runoff.
Various forms of porous pavement options are also now available where water can be retained rather than run off. Vail pointed out that Stewart Airport in Newburgh, N.Y. uses one version in a large parking lot. Responding to a question from Anne Impellizzeri about problems with snow plowing and porous surfaces, Vail said special considerations were necessary. For instance, it is important to reduce salt usage to protect ground water and to limit the use of sand, which can clog the pores of such surfaces. Snowplows need to be held higher to avoid scraping off the surface. On the other hand, Vail pointed out that ice is less likely to form on a surface that allows for infiltration than on impervious asphalt pavement. Noting the draft comprehensive plan promotes walking in Cold Spring through more sidewalks, Mike Armstrong asked about porous alternatives. Vail said Syracuse, N.Y. had already installed a version as part of a demonstration project. While absorbent sidewalk alternatives are new, they offer promising results, Vail said.
Connecting a rain barrel or cistern at the end of a gutter to conserve water for gardening, car washing and other tasks is yet another way to preserve fresh water and stem the tide of storm water according to Vail. In response to a question from Mike Armstrong, Vail said some cities, including New York City, have offered free rain barrels as a way to promote usage. The barrels come with screened covers to prevent mosquito infestation and keep out falling leaves. Directing gutter spouts to a garden or soiled surface, as opposed to an impervious surface such as a driveway, is another more natural solution to abating storm water runoff, Vail added.
Vail also pointed out that the Cold Spring draft comprehensive plan contained many references to green infrastructure thinking. Open space preservation, flood plain protection, clarifying ownership of properties near brooks, mapping the storm drain system, maintaining open corridors, wetlands protection measures and a resource analysis map were among the plan elements that, in her view, properly demonstrate appreciation for green alternatives to conventional planning.
Buffering streams and tributaries with specially selected shrubs and trees is another method for protecting against storm water volume and its potential damage. Beth Roessler, riparian buffer coordinator for the DEC, told the board the agency sponsors the Trees for Tribs program, which plants, at no charge, specially selected buffer areas along streams in communities that propose projects meeting the criteria, including providing volunteers for the planting work and monitoring afterwards. Roessler said the DEC favors public property projects but also entertains private property applications where a public good is involved. In 2008, Trees for Tribs installed a buffer to help curtail chronic flooding at the Spring Brook Condominiums on Fair Street.
Photo by K. Foley